Refactoring

Src/Myc.Core.Signals.pas

@@ -12,7 +12,7 @@ type
     protected
         function GetIsSet: Boolean; virtual; abstract;
     public
-        function Subscribe(Subscriber: IMycSubscriber): TMycSubscription; virtual; abstract;
+        function Subscribe(Subscriber: IMycSubscriber): Pointer; virtual; abstract;
         procedure Unsubscribe(Tag: TMycNotifyList<IMycSubscriber>.TTag); virtual; abstract;
         property IsSet: Boolean read GetIsSet;
     end;
@@ -23,7 +23,7 @@ type
     protected
         // IMycState
         function GetIsSet: Boolean;
-        function Subscribe(Subscriber: IMycSubscriber): TMycSubscription;
+        function Subscribe(Subscriber: IMycSubscriber): Pointer;
         procedure Unsubscribe(Tag: TMycNotifyList<IMycSubscriber>.TTag);
     public
         constructor Create;
@@ -38,7 +38,7 @@ type
         FSubscribers: TMycNotifyList<IMycSubscriber>; // List of subscribers waiting for this latch to be set.
     private
         [volatile] FCount: Integer; // The internal countdown value for the latch.
-        function GetState: IMycState; // Implementation for IMycLatch.GetState and IMycFlag.GetState.
+        function GetState: TState; // Implementation for IMycLatch.GetState and IMycFlag.GetState.
     protected
         function GetIsSet: Boolean; override; final;  // Implementation for IMycState.GetIsSet.
     public
@@ -48,7 +48,7 @@ type
         destructor Destroy; override;
 
         // IMycSignal implementation
-        function Subscribe(Subscriber: IMycSubscriber): TMycSubscription; override;
+        function Subscribe(Subscriber: IMycSubscriber): Pointer; override;
         procedure Unsubscribe(Tag: TMycNotifyList<IMycSubscriber>.TTag); override;
 
         // IMycSubscriber implementation for TMycLatch itself.
@@ -59,7 +59,7 @@ type
 
     TMycNullLatch = class( TInterfacedObject, IMycLatch )
     private
-        function GetState: IMycState;
+        function GetState: TState;
         function Notify: Boolean;
     end;
 
@@ -71,7 +71,7 @@ type
         FSubscribers: TMycNotifyList<IMycSubscriber>; // List of subscribers interested in state changes of this dirty flag.
     private
         [volatile] FFlag: Boolean; // Internal state: true if dirty/set, false if clean/reset.
-        function GetState: IMycState; // Implementation for IMycFlag.GetState.
+        function GetState: TState;
     protected
         function GetIsSet: Boolean; override; final;  // Implementation for IMycState.GetIsSet (true if dirty).
     public
@@ -82,7 +82,7 @@ type
         // Factory method to create a new TMycDirty instance.
         class function CreateDirty: IMycDirty; static;
 
-        function Subscribe(Subscriber: IMycSubscriber): TMycSubscription; override;
+        function Subscribe(Subscriber: IMycSubscriber): Pointer; override;
         procedure Unsubscribe(Tag: TMycNotifyList<IMycSubscriber>.TTag); override;
 
         // IMycSubscriber implementation for TMycDirty.
@@ -95,7 +95,7 @@ type
 
     TMycNullDirty = class( TInterfacedObject, IMycDirty )
     private
-        function GetState: IMycState;
+        function GetState: TState;
         function Notify: Boolean;
         function Reset: Boolean;
     end;
@@ -117,7 +117,7 @@ begin
     Result := true; // Null state is always set.
 end;
 
-function TMycNullState.Subscribe(Subscriber: IMycSubscriber): TMycSubscription;
+function TMycNullState.Subscribe(Subscriber: IMycSubscriber): Pointer;
 begin
     // Since the state is always set, notify the subscriber immediately.
     if Assigned(Subscriber) then
@@ -125,7 +125,7 @@ begin
         Subscriber.Notify;
     end;
     // No ongoing subscription is necessary or meaningful for a null state.
-    Result.Create(Self, nil); // Return an empty subscription.
+    Result := nil;
 end;
 
 procedure TMycNullState.Unsubscribe(Tag: TMycNotifyList<IMycSubscriber>.TTag);
@@ -135,7 +135,7 @@ end;
 
 { TMycNullLatch }
 
-function TMycNullLatch.GetState: IMycState;
+function TMycNullLatch.GetState: TState;
 begin
     Result := TState.Null;
 end;
@@ -202,13 +202,13 @@ begin
     Result := FCount <= 0;
 end;
 
-function TMycLatch.GetState: IMycState;
+function TMycLatch.GetState: TState;
 begin
     // TMycLatch itself implements IMycState.
-    exit(Self);
+    Result := Self;
 end;
 
-function TMycLatch.Subscribe(Subscriber: IMycSubscriber): TMycSubscription;
+function TMycLatch.Subscribe(Subscriber: IMycSubscriber): Pointer;
 var
     alreadySet: Boolean;
 begin
@@ -227,7 +227,7 @@ begin
         else
         begin
             // If not yet set, advise the subscriber.
-            Result.Create(Self, FSubscribers.Advise(Subscriber));
+            Result := FSubscribers.Advise(Subscriber);
         end;
     finally
         FSubscribers.Release;
@@ -249,7 +249,7 @@ end;
 
 { TMycNullDirty }
 
-function TMycNullDirty.GetState: IMycState;
+function TMycNullDirty.GetState: TState;
 begin
     Result := TState.Null;
 end;
@@ -297,10 +297,10 @@ begin
     Result := FFlag;
 end;
 
-function TMycDirty.GetState: IMycState;
+function TMycDirty.GetState: TState;
 begin
     // TMycDirty itself implements IMycState.
-    exit(Self);
+    Result := Self;
 end;
 
 function TMycDirty.Notify: Boolean;
@@ -329,7 +329,7 @@ begin
     end;
 end;
 
-function TMycDirty.Subscribe(Subscriber: IMycSubscriber): TMycSubscription;
+function TMycDirty.Subscribe(Subscriber: IMycSubscriber): Pointer;
 begin
     if not Assigned(Subscriber) then
         exit;
@@ -341,7 +341,7 @@ begin
     FSubscribers.Lock;
     try
         // Add subscriber regardless of current state.
-        Result.Create(Self, FSubscribers.Advise(Subscriber));
+        Result := FSubscribers.Advise(Subscriber);
         if FFlag then // If currently dirty, notify the new subscriber immediately.
         begin
             Subscriber.Notify;